Delay line having non planar ground plane, each loop bracketing two runs of meandering signal line

ABSTRACT

An electrical component such as a delay line comprising a first signal conductor and a second signal conductor spatially displaced from and electrically cooperable with said first signal conductor. At least one of said first or second signal conductors extending through an enclosure of nonconductive material having nonplanar upper and lower surfaces to provide increased isolation between an input and an output signal. A method of making the electrical component also is disclosed.

United States Patent [72] Inventors Edwin S. Eichert Bryn Mawr; WilliamT. Storey, lI, West Chester, both of, Pa. [2]] Appl. No. 720,998 [22]Filed Apr. 12, 1968 [45] Patented May 25, 1971 [73] Assignee Technitrol,Inc.

Philadelphia, Pa.

[54] DELAY LINE HAVING NON PLANAR GROUND PLANE, EACH LOOP BRACKETING TWORUNS OF MEANDERING SIGNAL LINE 9 Claims, 7 Drawing Figs.

[52] US. Cl 333/31, 333/6, 333/84, 333/96, 174/36 [51] Int. Cl H0lp5/12, l-IOip 3/02,l-l01p 3/08 [50] Field of Search 333/31, 84 (M), 84,95 (A), 96, 24.1; 174/28, 29

[56] References Cited UNITED STATES PATENTS 2,462,887 3/1949 Muller174/28X 2,903,695 9/1959 Jamieson.... 333/84(M) 2,994,050 7/1961 Ayer eta1. 333/84(M) 2,997,519 8/1961 Hines et al.. 333/96X 3,004,229 10/1961Stearns 333/84(M) 3,257,629 6/1966 Kornreich 333/31 3,260,972 7/1966Pusch 333/84(M) 3,287,490 11/1966 Wright 333/96X 3,417,279 12/1968Chodorow 333/31X 3,448,410 6/1969 Parks 333/31 FOREIGN PATENTS 496,67212/1938 Great Britain..... 174/28 921,232 3/1963 Great Britain 174/28OTHER REFERENCES Gordon; S. H., A Miniature Monostrip Delay Line forNanosecond Pulses, Electronic Design News, Dec. 1963, pp. 32- 39,333/84(M) Dodge; Phelps, Advertisement in The Microwave Engs. Handbookand Buyers Guide" 1964, p. A-74 MacKenzie et al. Some Fundamental DesignPrinciples for the Development of Precision Coaxial Standards &Components" IEEE Trans. on Microwave Theory & Techniques, Vol. MTT14 #1,Jan. 1966, pp. 29-39 Cohn; S. B., Shielded Coupled-Strip TransmissionLine", IEEE Trans. on Microwave Theory & Techniques, Vol. MTT- 3, Oct.1955, pp. 29 38 Primary Examiner-Herman Karl Saalbach AssistantExaminer-Wm. H. Punter Att0rney-Yuter and Fields ABSTRACT: An electricalcomponent such as a delay line comprising a first signal conductor and asecond signal conductor spatially displaced from and electricallycooperable with said first signal conductor. At least one of said firstor second signal conductors extending through an enclosure ofnonconductive material having nonplanar upper and lower surfaces toprovide increased isolation between an input and an output signal.

A method of making the electrical component also is disclosed.

WENT-EU mwzslan 358L250 SHEET 1 [1F 2 INVENTORS Edwin S.Eicherf 53William T. Srorey,1I

ATTORNEYS DELAY LINE HAVING NON PLANAR GROUND PLANE,

EACH LOOP BRACKETING TWO RUNS OF MEANDERING SIGNAL LINE This inventionrelates generally to an electrical component and to a method of makingthe same and, more particularly, pertains to an electrical componentthat may be used as a delay line that provides substantial isolationbetween input and output signals.

Presently, so-called lumped constant transmission lines or distributedconstant coaxial lines are utilized as signal delay lines to delay thetime of arrival of a signal at a particular point in a circuit. However,these devices inherently are bulky and are uneconomic in terms of bothcost and space since many feet of coaxial cable, for example, arerequired to obtain delay magnitudes of the order of tenths ofmilliseconds. The present trend toward miniaturization of circuits hasproduced a need for corresponding miniaturized delay lines. While anumber of such delay lines have been proposed, they have numerousdisadvantages associated with their use. For example, such delay lineshave been found to introduce considerable distortion, provide long risetimes, and lack isolation between the input and output circuits.

Accordingly, an object of the present invention is to provide animproved delay line.

A more specific object of the present invention is to provide aminiaturized electrical component which may be used as a transmissionline or a delay line.

Another object and feature'of the present invention resides in the noveldetails of construction which provide a delay line of the type describedhaving a high magnitude of isolation between the input and outputcircuits.

A further object is to provide an electrical component which is economicto fabricate and reliable in operation.

Accordingly, an electrical component constructed according to thepresent invention comprises signal conducting means for conducting anelectric signal. An enclosure of nonconductive material surrounds atleast a portion of the signal conducting means and is provided with anupper anda lower surface. At least one of the upper and lower surfacescomprises nonplanar portions juxtaposed across the length of theenclosure to provide the component with desired characteristics.

At present, many of the above-described miniature electrical componentssuch as transmission or delay lines are made by laminating together thevarious elements comprising the particular line. However, this method isan expensive and time consuming operation.

Accordingly, another object of this invention is to provide an improvedmethod for making an electrical component of the type described.

Thus, a method of making an electrical component in accordance with thisaspect of the invention includes encapsulating a signal conductor withina block of nonconducting material having a dielectric constantsubstantially independent of frequency, low dielectric loss and amagnetic permeability greater than unity. The method further includesforming the block with upper and lower surfaces comprising nonplanarportions juxtaposed across its length.

Other features and advantages of the present invention will become moreapparent from a consideration of the following detailed description whentaken in conjunction with the accompanying drawings, in which:

FIG. 1 is a top elevational view of aconducting plate having a signalconductor traced thereon, to an enlarged scale;

FIG. 2 is a perspective view with parts broken away, of an electricalcomponent constructed according to the present invention;

FIG. 3 is a vertical sectional view taken along the line 33 of FIG. 2;

FIG. 4 is a top plan view of a modified embodiment of an electricalcomponent constructed in accordance with the present invention;

FIG. 5 is a sectional view thereof taken along the line 55 of FIG. 4;

FIG. 6 is a sectional view ofa further modified embodiment of anelectrical component taken along the line 6-6 of FIG. 7; and

FIG. 7 is a sectional view of the embodiment of FIG. 6 taken along theline 7-7 thereof.

While the present invention has applicability both as a delay line or atransmission line, it will be described as a delay line. However, it isto be understood that this is by way of example only and not by way oflimitation. That is, the electrical components and methods of making thesame described hereinbelow apply to delay lines and/0r transmissionlines.

A delay line constructed in accordance with the present invention isdesignated generally by the reference numeral 10 in FIG. 2 and includesan electrical signal conductor 12 which extends through an enclosure orhousing 14. The housing I4, which includes a lower section 13 and anupper section 15, is fabricated from a nonconductive material which, inpractice, has a high permcabilitypermittivity product which issubstantially frequency independent (e.g., substantially less than a 5percent change over a frequency range of from I megahertz to lgigahertz). Moreover, the material forming the housing 14 should have alow dielectric and magnetic loss over the noted range of frequencies.Thus, a ferrite material may be used for the housing since it exhibitssuch properties. Alternatively, another material which exhibits theseproperties is a plastic matrix in which is dispersed a magneticmaterial.

A suitable plastic would be one having the characteristics of asubstantially frequency independent dielectric constant and a lowdielectric loss. It has been found that plastics such as: Mylar,Polyethylene; Polystyrene, Rexalite i422, Styrloy 22; and Vibron I40satisfy the above criteria. In practice, a polytetrafluoroethyleneplastic is ideally suitable for use. The magnetic material embedded inthe plastic matrix can be either a ferromagnetic or a ferrimagneticmaterial. More specifically, powdered iron or powdered ferrite ispreferred.

The signal conductor 12 is provided with an input arm or lead 16 whichis adapted to be connected to appropriate input circuitry (not shown),and an output arm or lead 18, which is adapted to be connected toappropriate output circuitry (not shown). Between the input and theoutput arms 16 and 18 the signal conductor 12 traces out a meanderingpath. More particularly, the signal conductor 12 is formed by aplurality of pairs of interdigit elements 12A and 128, which are inadjacent and substantially parallel relationship and which areinterconnected serially by respective serial elements 12C. Additionally,the serial elements are connected with transversely extending arms orleads 12D which extend beyond the side edges of the housing 14 toprovide a plurality of taps which are spaced throughout the length ofthe delay line, to obtain corresponding different time delays. Morespecifically, the distance between any one of the taps 12D and the inputlead 16 is proportional to the delay time. Hence, by connecting theoutput circuit to respective ones of the taps 12D different delay timesmay be had.

The lower surface of the lower section 13 and the upper surface of theupper section 15 comprise a plurality of convex portions 13A and 15A,respectively, juxtaposed across the lengths of the respective sections.As shown in FIG. 3, the portions 13A and 15A are in a one-to-onecorrespondence and respective portions are aligned with each other toprovide sets of opposed convex portions. Additionally, in the embodimentshown, each set comprising opposed portions 13A, ISA is sized andpositioned to bracket a different pair of interdigit elements. Forexample, the right-hand portions 13A, 15A, as taken in FIGS. 2 and 3,bracket the right-hand interdigit elements 12A and 12B, and theleft-hand portions 13A, 15A

bracket the left-hand elements 12A, 123. The convexity of the upper andlower surfaces provide substantial isolation between the input and theoutput circuits connected to the delay line 10. Moreover, the lengths ofthe interdigit elements and the spacing between the elements 12A, 128comprising any pair which is bracketed by a set ISA, 15A of curvedsurfacescontrols the coefficient of coupling between the elementstandcan be used to vary the properties of the delay line.

Alternatively, the convex portions and/or the interdigit elements 12A,128 may be sized and positioned so that each set of convex portions 13A,15A brackets more than two interdigit elements in accordance with thedesired characteristics of the line.

The upper and lower surfaces of the respective upper and lower sections15 and 13 are covered with respective upper and lower conductive layersand 22 which conform to the curvature of these surfaces. The layers 20and 22 may be connected together and to ground by a lead 24 to providerespective ground plane elements. On the other hand, the layers 20 and22 may extend completely about the housing 14 so that they areelectrically connected together without the need for an external wire.In this latter embodiment, appropriate provision is made so that theleads l6, l8 and 12D do not contact the layers 20, 22, in anyconventional manner.

Signals applied between the input arm or lead l6 and one or bothgrounded layers 20, 22 travel along the signal conductor l2 and aretransmitted as delayed signals across the output arm or lead 18 andground or across any one of the respective transverse taps 12D andground. The transmitted signals will be delayed a period of time relatedto the mechanical length of the signal conductor 12 between the arm 16and the arm 18 or the selected tap 12D, and the electromagneticproperties such as the permeability and the permittivity of the regionsurrounding the conductor 12. Thus, greater delays per unit length areobtained from the meandering geometry of the signal conductor. Inaddition, increasing the product of the average permeability and averagepermittivity of the region surrounding the signal conductor 12 increasesthe delay per unit length.

A method for fabricating the delay line 10 includes tracing the signalconductor 12 on a conducting plate 26 (HO. 1)

which may be made of aluminum or copper or a similar metal. A marginalarea 28 to which arms 12D extend is similarly traced on the conductingplate. The signal conductor 12 including the marginal area 28 then isremoved from the remainder of the metal plate by etching or stamping ora similar procedure. The resulting conductor and attached marginal area28 may be silvered on both surfaces to decrease the rise time of theresultant delay line.

A mold comprising two halves or sections is provided. The bottom surfaceof each section of the mold comprises convex portions juxtaposed acrossthe length of the mold. Each section is filled with a potting compoundcomprising one of the above-noted plastics such aspolytetrafiuoroethylene in particulate form having the powdered magneticmaterial dispersed therein. Alternatively, the mold sections may befilled with a powdered ferrite material or any other material having thedesired properties.

The conductor 12 having the marginal area 28 connected thereto ispositioned on one of the mold sections so that the marginal area 28forms a seal when the mold halves are closed. The mold is then closed.It is to be noted that the material from the top section of the moldfills the spaces between the elements comprising the signal conductor12.

Heat is applied to the mold to melt the particular mixture or materialused so that the material completely surrounds the conductor 12. Themold is allowed to cool so that the material solidifies about theconductor 12 to form the enclosure 14 through which the conductorextends. The resulting product then is removed from the mold and themarginal area 28 broken away to provide a conformally potted delay linehaving substantial isolation between input and output due to thecurvature of the upper and lower surfaces.

The upper and lower surfaces of the enclosure or housing 14 are coatedwith a metal by spraying or any other conventional method to form theconductive layers 20 and 22.

Accordingly, an electrical component and a method of making the same hasbeen disclosed which is simple to construct and economic to produce, andwhich provides substantial isolation between the input and outputcircuits.

It is to be understood that the present invention also includes aconstruction similar to that illustrated in FIGS. l--3, but one in whicheach set of opposed curved portions 13A, ISA brackets a singleinterdigit element 12A or 128. That is, the convex portions 13A, 15A aresized to encompass only one interdigit element. Thus, for a delay lineof the type shown in FIG. 3 which includes six interdigit elements, sixsets of opposed convex portions would be providcd. However, it isobvious, for this latter construction that the properties of the delayline cannot be varied by changing the spacing between interdigitelements because they effectively are isolated from each other.

Moreover, it is emphasized that the convex surfaces shown are forillustrative purposes only and are not to be interpreted as a limitationof the present invention. That is, the invention contemplates anenclosure having nonplanar upper and lower surfaces. To put this anotherway, the distance of the surfaces from the plane of the conductor orlead 12, as measured along a normal to the plane, varies from a minimumto a maximum value for each interdigit element or elements bracketed bya respective set of nonplanar surfaces.

A modified embodiment of a delay line constructed according to thepresent invention and one in which each interdigit element is isolatedfrom the adjacent elements is shown in FIGS. 4 and 5 and designatedgenerally by the reference numeral 30. The delay line 30 includes asignal conductor 32 which traces out a meandering or sinuous path asshown. The conductor 32 is enclosed within an enclosure or housing 34having the same meandering or sinuous shape as the conductor. Thehousing 34 is nonconductive, has a high permeabilitypermittivity productwhich is substantially frequency independent over the usable bandwidth,and has low dielectric and magnetic losses over therange of frequenciesof use. Accordingly, the housing 34 may be fabricated from any of thematerials noted above with respect to the housing 14. The ends of theconductor 33 extend beyond the housing 34 to provide respective inputand output leads 36 and 38. Additionally, the conductor 32 is providedwith a plurality of taps 37 similarly to the taps 12D of the conductor12.

The housing 34 includes interconnected parallel sections 34A whichsurround the parallel interdigit elements of the conductor.Additionally, each section 34A and the interconnecting portions of thehousing are substantially circular in cross section, as shown in FIG. 5,thereby to provide substantial isolation between adjacent elements ofthe conductor 32 and between the input and output leads. in other words,the top and bottom surfaces of the housing 34 are convex similarly tothe housing 14.

Provided on the outer surface of the housing 34 is a metal coating 40which functions as a ground plane element for the delay line. I

The delay line 30 may be manufactured in the same manner as the delayline 10. More specifically, the conductor 32 is produced by tracing theconductor on a conductive sheet and removing the same from the sheet. Ifdesired the conductor 32 may be coated with silver on one or both sidesto reduce rise times. Mold sections having respective semicircular upperand lower surfaces are filled with a potting compound such as a ferritematerial or any of the other materials noted, and the signal conductor32 is placed on one section of the mold. The mold is then closed andheated. Thereafter, the mold is cooled and the delay line 30 is removedtherefrom and coated with a conductive layer such as silver to provide aconformally molded delay line having substantial isolation between theinput and output leads.

FIGS. 6 and 7 illustrate a balanced transmission or delay lineconstruction wherein two spatially displaced conductor leads 42 and 44extend through the enclosure or housing 40. More specifically, thebalanced construction of FIGS. 6 and 7 includes the enclosure 40 ofdielectric material. The composi- I tion of the enclosure 40 maycomprise any of the materials specified above such as ferrite, or aplastic matrix of the type noted in which is dispersed a magneticmaterial.

The signal conductors or leads 42 and 44 are similar in construction tothe signal conductor 12. Accordingly, the conductors 42, 44 respectivelyinclude: input arms 46, 48; output arms 50, 52', pairs of interdigitelements 42A, 42B and 44A, 44B; and serial interconnecting elements 42C,44C. Moreover, the conductors 42, 44 may be provided with trans versetapsv As shown in FIG. 6, corresponding elements of the leads orconductors 42 and 44 are in substantially adjacent parallelrelationship.

Additionally, the upper and lower surfaces of the enclosure 40 compriserespective sets of nonplanar or convex portions 40A and 40B juxtaposedacross the length of each enclosure. As shown in FIG. 7, each set ofportions 40A, 40B brackets a pair of interdigit elements 42A, 44A and42B, 44B of the conductors 42 and 44. However, as in the embodiment ofFIG. 2,

more or less then a pair of interdigit elements may be bracketed by aset of nonplanar portions. Thus, the embodiment of FIGS. 6 and 7provides a balanced line in which there is substantialisolation betweena signal applied to inputs 46 and 48 and the signal taken from outputs50 and 52.

Additionally, although the device of FIGS. 6 and 7 is balanced, in manyapplications it may be desirable to contain the electric field producedby the signal carried by the leads within the enclosure 40 or to shieldthe leads from external electric fields. Accordingly, conductive layers54 may be provided on the enclosure 40 to effect such shielding.

The balanced line embodiment of FIGS. 6 and 7 may be made by utilizingthe method described above in conjunction with the device of FlGS. 2 and3. More specifically, the conductors 42 and 44 are traced on aconducting plate and are connected by a marginal area. The conductorsand the mar- "ginal area are then separated from the remainder of theplate and may be silvered. Mold halves having nonplanar bottom walls arefilled with the material comprising the enclosure 40 and the leads areplaced over one mold half so that the marginal area forms a seal whenthe mold is closed. The mold halves are closed so that the dielectricmaterial falls about and between the conductors. Heat is then applied tomelt the material to form the balanced line.

After the mold has cooled the component is removed therefrom and themarginal area is separated from the extending portions of the signalconductors. If desired, the enclosure then may be coated with a metalfor shielding purposes.

While preferred embodiments and methods of making the present inventionhave been shown and described herein it will be obvious that numerousomissions, changes and additions may be made in such embodiments andmethods without departing from the spirit and scope of the invention.

What we claim is:

1. An electrical component comprising signal conducting means forconducting an electrical signal, an enclosure of nonconductive materialsurrounding at least a portion of said signal conducting means andhaving an upper and a lower surface, at least one of said upper andlower surfaces comprising a plurality of nonplanar portions juxtaposedacross the length of said enclosure, said signal conducting meansincluding a first signal conductor and a second signal conductorspacially displaced from said first signal conductor and electricallycooperable therewith, said first signal conductor being formed by aplurality of pairs of serially connected interdigit elements which arein adjacent and substantially parallel relationship, and at least one ofsaid plurality of nonplanar portions brackets at least one of saidplurality of pairs of interdigit elements.

2. An electrical component comprising signal conducting means forconducting an electric signal, an enclosure of nonconductive materialsurrounding at least a portion of said signal conducting means andhaving an upper and a lower surface, at least one of said upper andlower surfaces comprising a plurality of nonplanar portions juxtaposedacross the length of said enclosure, said signal conducting meansincluding a first signal conductor and a second signal conductorspacially displaced from said first signal conductor and electricallycooperable therewith, said first signal conductor being formed by aplurality of pairs of serially connected interdigit elements which arein adjacent and substantially parallel relationship, said plurality ofnonplanar portions each comprising a convex section, each of said convexsections being sized to bracket a respective pair of said interdigitelements.

3. An electrical component comprising signal conducting means forconducting an electric signal; said signal conducting means including afirst signal conductor and a second signal conductor spacially displacedfrom said first signal conductor and electrically cooperable therewith;an enclosure of nonconducting material surrounding at least a portion ofsaid signal conducting means and having an upper and a lower surface;said material having a dielectric constant substantially independent offrequency, low dielectric loss and a magnetic permeability greater thanunity; said upper and lower surfaces comprising a plurality of nonplanarportions juxtaposed across the length of said enclosure, said firstsignal conductor comprising a plurality of pairs of serially connectedinterdigit elements which are in adjacent and substantially parallelrelationship, each one of said nonplanar portions of said upper surfacebeing defined by indentations which are aligned with and spaced fromindentations defining a respective nonplanar portion of said lowersurface to provide a plurality of sets of aligned nonplanar portions,said sets and said interdigit elements being sized and positioned sothat at least a pair of interdigit elements is received within each setof nonplaner portions.

4. An electrical component as in claim 3, in which said second signalconductor comprises electrically conductive elements connected to saidupper and lower surfaces and conforming to the shape of said nonplanarportions.

5. An electrical component as in claim 3, and a plurality of taps onsaid first signal conductor extending beyond said enclosure and adaptedto be connected to respective output circuits.

6. An electrical component as in claim 3, in which said first signalconductor includes an upper and a lower surface, and a coating of silvermaterial on said upper and lower surfaces of said first signalconductor.

7. An electrical component as in claim 3, in which said nonplanarportions are convex in shape.

8. An electrical component as in claim 7, in which said second signalconductor comprises a plurality of pairs of serially connectedinterdigit'elements which are in adjacent and substantially parallelrelationship, each one of said interdigit elements of said first signalconductor being positioned adjacent to a respective interdigit elementof said second signal conductor, said first and second signal conductorsand said sets of nonplanar portions being sized and positioned so thateach set of convex portions bracket at least an interdigit element ofsaid first signal conductor and an interdigit element of said secondsignal conductor.

9. An electrical component as in claim 8, and electrically conductiveelements connected to said upper and lower surfaces.

1. An electrical component comprising signal conducting means forconducting an electrical signal, an enclosure of nonconductive materialsurrounding at least a portion of said signal conducting means andhaving an upper and a lower surface, at least one of said upper andlower surfaces comprising a plurality of nonplanar portions juxtaposedacross the length of said enclosure, said signal conducting meansincluding a first signal conductor and a second signal conductorspacially displaced from said first signal conductor and electricallycooperable therewith, said first signal conductor being formed by aplurality of pairs of serially connected interdigit elements which arein adjacent and substantially parallel relationship, and at least one ofsaid plurality of nonplanar portions brackets at least one of saidplurality of pairs of interdigit elements.
 2. An electrical componentcomprising signal conducting means for conducting an electric signal, anenclosure of nonconductive material surrounding at least a portion ofsaid signal conducting means and having an upper and a lower surface, atleast one of said upper and lower surfaces comprising a plurality ofnonplanar portions juxtaposed across the length of said enclosure, saidsignal conducting means including a first signal conductor and a secondsignal conductor spacially displaced from said first signal conductorand electrically cooperable therewith, said first signal conductor beingformed by a plurality of pairs of serially connected interdigit elementswhich are in adjacent and substantially parallel relationship, saidplurality of nonplanar portions each comprising a convex section, eachof said convex sections being sized to bracket a respective pair of saidinterdigit elements.
 3. An electrical component comprising signalconducting means for conducting an electric signal; said signalconducting means including a first signal conductor and a second signalconductor spacially displaced from said first signal conductor andelectrically cooperable therewith; an enclosure of nonconductingmaterial surrounding at least a portion of said signal conducting meansand having an upper and a lower surface; said material having adielectric constant substantially independent of frequency, lowdielectric loss and a magnetic permeability greater than unitY; saidupper and lower surfaces comprising a plurality of nonplanar portionsjuxtaposed across the length of said enclosure, said first signalconductor comprising a plurality of pairs of serially connectedinterdigit elements which are in adjacent and substantially parallelrelationship, each one of said nonplanar portions of said upper surfacebeing defined by indentations which are aligned with and spaced fromindentations defining a respective nonplanar portion of said lowersurface to provide a plurality of sets of aligned nonplanar portions,said sets and said interdigit elements being sized and positioned sothat at least a pair of interdigit elements is received within each setof nonplaner portions.
 4. An electrical component as in claim 3, inwhich said second signal conductor comprises electrically conductiveelements connected to said upper and lower surfaces and conforming tothe shape of said nonplanar portions.
 5. An electrical component as inclaim 3, and a plurality of taps on said first signal conductorextending beyond said enclosure and adapted to be connected torespective output circuits.
 6. An electrical component as in claim 3, inwhich said first signal conductor includes an upper and a lower surface,and a coating of silver material on said upper and lower surfaces ofsaid first signal conductor.
 7. An electrical component as in claim 3,in which said nonplanar portions are convex in shape.
 8. An electricalcomponent as in claim 7, in which said second signal conductor comprisesa plurality of pairs of serially connected interdigit elements which arein adjacent and substantially parallel relationship, each one of saidinterdigit elements of said first signal conductor being positionedadjacent to a respective interdigit element of said second signalconductor, said first and second signal conductors and said sets ofnonplanar portions being sized and positioned so that each set of convexportions bracket at least an interdigit element of said first signalconductor and an interdigit element of said second signal conductor. 9.An electrical component as in claim 8, and electrically conductiveelements connected to said upper and lower surfaces.